3) A 60-year-old obese diabetic man, treated for the last ten years with various oral hypoglycemic agents comes to you in routine follow-up. One year ago, he suffered an acute MI and CHF (LVEF <30%), he was started on Aspirin, a beta-blocker, and an ACE inhibitor. Recently his family doctor added a new agent for his CHF. Electrolytes obtained now revealed a potassium level of 7.0 mEq/L. The acute rise in the serum potassium level most likely is due to:

A) The beta-blocker
B) The ACE-inhibitor
C) Eplerenone
D) Digoxin

4) A 50-year-old woman received a cadaveric kidney transplant 5 years ago. Serum creatinine has gradually risen only the last three years to its present level of 2.6 mg/dl. She takes a low dose of prednisone, MMF and cyclosporine. She has mild hypertension and her serum [K+] level typically ranges between 5.3 and 5.8 mEq/L. The most appropriate treatment for the hyperkalemia is: